Method and apparatus for humidification and warming of air

ABSTRACT

A method of humidifying a gas that includes supplying a gas to a surface of a humidification material that readily absorbs moisture and readily releases moisture when exposed to a dry environment and generating turbulence in the gas as it passes over the surface of the humidification material.

RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 11/248,412 (still pending), filed Oct. 12, 2005, which is acontinuation of U.S. patent application Ser. No. 09/896,821 (now U.S.Pat. No. 6,976,489), filed Jun. 29, 2001, which claims priority to U.S.Provisional Pat. App. No. 60/215,442, filed Jun. 30, 2000, the entiretyof each of which are hereby incorporated by reference. The presentapplication is related to U.S. patent application Ser. No. 11/649,641(still pending), filed Jan. 4, 2007, which is a continuation of U.S.patent application Ser. No. 11/248,412 (still pending), filed Oct. 12,2005, which is a continuation of U.S. patent application Ser. No.09/896,821 (now U.S. Pat. No. 6,976,489), filed Jun. 29, 2001, whichclaims priority to U.S. Provisional Pat. App. No. 60/215,442, filed Jun.30, 2000, the entirety of each of which are hereby incorporated byreference.

BACKGROUND

1. Field of the Invention

The present invention relates to an apparatus and method used tohumidify and/or warm a gas prior to its use in a surgical or othermedical procedure.

2. Discussion of Related Art

Many medical and surgical procedures require the supply to a patient ofwarmed and/or humidified gas at constant high flow rates. Ideally, theflow rate should be approximately 20 liters per minute, the relativehumidity should be approximately 80 to 100 percent, and the temperatureapproximately 90 to 105 degrees Fahrenheit. Most prior art devicescannot meet or exceed these ideal characteristics. The flow rate of manyprior devices is well below 20 liters per minute. Commonly, the flowrate of prior devices has been generally 12 to 14 liters per minute.Most of these devices generally operate by forcing the gas through thehumidification material, thereby requiring a high degree of pressure.This increased pressure reduces the flow rate of the gas even further.

SUMMARY OF INVENTION

One aspect of the present invention regards a gas humidificationapparatus that includes an inlet, a humidification device in fluidcommunication with the inlet, the humidification device having ahumidification material that readily absorbs moisture and readilyreleases moisture when exposed to a dry environment, wherein thehumidification material has a configuration that generates turbulence ina gas as it passes over a surface of the humidification material and anoutlet in fluid communication with the humidification device.

A second aspect of the present invention regards a gas humidificationapparatus that includes an inlet, a humidification device in fluidcommunication with the inlet, the humidification device having ahumidification material that readily absorbs moisture and readilyreleases moisture when exposed to a dry environment, wherein thehumidification material is placed within a shell that has aconfiguration that generates turbulence in a gas as it passes over asurface of the shell and an outlet in fluid communication with thehumidification device.

A third aspect of the present invention regards a gas humidificationapparatus that includes an inlet, a humidification device in fluidcommunication with the inlet, the humidification device having a heaterhousing that includes a heater and a plurality of openings. Ahumidification material that readily absorbs moisture and readilyreleases moisture when exposed to a dry environment and an outlet influid communication with the humidification device.

A fourth aspect of the present invention regards a gas humidificationapparatus that includes inlet means for supplying a gas, turbulencemeans for generating turbulence in the gas and outlet means forexpelling the turbulent gas from the gas humidification apparatus.

A fifth aspect of the present invention regards a method of humidifyinga gas that includes supplying a gas to a surface of a humidificationmaterial that readily absorbs moisture and readily releases moisturewhen exposed to a dry environment and generating turbulence in gas as itpasses over the surface of the humidification material.

A sixth aspect of the present invention regards a method of humidifyinga gas that includes warming a gas, humidifying the gas and placing acatheter in fluid communication with the gas during the humidifying.

A seventh aspect of the present invention regards a gas apparatus thatincludes an inlet, a heater in fluid communication with the inlet and atemperature sensor for measuring a temperature of a gas that flowswithin the gas apparatus in an indirect manner.

An eighth aspect of the present invention regards a method ofhumidifying a gas that includes warming a gas, humidifying the gas andflowing the gas over a surface of a humidifier.

Each of the above aspects provides the advantage of supplying a patientwith warmed and/or humidified gas at or near preferred rates, humidityand/or temperature.

The foregoing and other features and advantages of the invention willbecome further apparent from the following detailed description of thepresently preferred embodiments, read in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 shows a first embodiment of a gas warmer and/or humidifierapparatus according to the present invention;

FIG. 2 shows a second embodiment of a gas warmer and/or humidifierapparatus according to the present invention having a plurality ofbaffles in the shell;

FIG. 3 shows a third embodiment of a gas warmer and/or humidifierapparatus according to the present invention having an externaltemperature or humidity sensor;

FIG. 4 shows a cross section perspective view of a gas warmer and/orhumidifier apparatus;

FIG. 5 shows a perspective exploded view of a fourth embodiment of gashumidification apparatus according to the present invention;

FIG. 6 shows a right top side perspective view of the gas humidificationapparatus of FIG. 5;

FIG. 7 shows a right bottom side perspective view of the gashumidification apparatus of FIG. 5;

FIG. 8 shows a top view of the gas humidification apparatus of FIG. 5;

FIG. 9 shows a right side view of the gas humidification apparatus ofFIG. 5;

FIG. 10 shows a front view of the gas humidification apparatus of FIG.5;

FIG. 11 shows a rear side perspective view of the gas humidificationapparatus of FIG. 5;

FIG. 12 shows a top view of an embodiment of a humidification materialto be used with the gas humidification apparatus of FIG. 5;

FIG. 13 shows a perspective view of a fifth embodiment of gashumidification apparatus according to the present invention;

FIG. 14 shows a side view of the gas humidification apparatus of FIG.13;

FIG. 15 shows a partially exposed side view of the gas humidificationapparatus of FIG. 13;

FIG. 16 shows a right front side and partially exposed perspective viewof the gas humidification apparatus of FIG. 13;

FIG. 17 shows a right rear side and partially exposed perspective viewof the gas humidification apparatus of FIG. 13; and

FIG. 18 shows a circuit diagram of heating circuit that can be used withthe gas humidification apparatus/gas warmer and/or heater apparatus ofFIGS. 1-17.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 shows one embodiment of the gas warmer and humidificationapparatus. FIG. 1 shows the apparatus used in conjunction with aninsufflation device. FIGS. 1-3 show the apparatus 1 associated with theinsufflation tubing 10. In a preferred embodiment, the apparatus islocated downstream from the gas source for the insufflation device wheredownstream refers to a location closer to output of the insufflationtubing 10 or a patient. The apparatus 1 has an upstream end locatednearer to the gas source and a downstream end located closer to thepatient. The gas warmer and humidifier apparatus 1 may be constructed asa re-useable or disposable product.

As shown in FIG. 1, in one embodiment, a gas inlet port 12 is located atan upstream end of the apparatus 1 and associable with the insulationtubing 10. A plurality of plugs 14 may also be located at the upstreamend of the apparatus 1. The plugs 14 may be male leads for associationwith the heater 18 and/or a thermocouple and/or other suitable sensingdevices. It is to be understood that the location at the upstream end isvariable and other locations consistent with the characteristics of theplugs 14 are envisioned.

As shown in FIGS. 1-3, the general arrangement of one embodiment of theapparatus 1 follows. The apparatus 1 includes a heater 18. Surroundingthe heater 18 is a core 20. The core 20 maintains the heater 18 in asignificantly watertight environment. About the core 20 is ahumidification material 24. The humidification material 24 generallyenvelops the entire core 20. The humidification material 24 may onlypartially envelop the core 20 as well. A shell 26, acting as a housing,surrounds humidification material 24. At the downstream end of theapparatus 1 may be a gas outlet 28 associable with a downstream portionof the insufflation tube 10.

The heater 18 of the above embodiment may include a conventionalcartridge heater, a heat generating wire, a light bulb, or other heatgenerating device capable of creating an elevated temperature that canradiate from the surface of the heater. As shown in FIG. 1, the heater18 is insertable within a core 20 of non-conductive material. In furtherembodiments, as shown in FIG. 2, the heater 18 and plugs 14 are moldedinto a single assembly that is then molded with the core 20 to make asingle unit.

The heater 18 can be a metal structure with integral sensing elements orexternal sensing elements. It can also be molded of a high temperatureresistant plastic. Either the metal or the plastic heater 18 isdisposable, although the lower cost of the plastic heater 18 may bettersuit it as a disposable heater 18. Further, the disposability orre-usability of the apparatus 1 aids in maintaining the apparatus 1sterile for any purposes that may require a sterile apparatus 1.

In a preferred embodiment, the heater 18 has approximately 36 watts ofpower although heaters 18 with other wattage, such as between 10 wattsand 50 watts, can also be used. The heater 18 typically is approximately1 to 5 inches long, preferably approximately 1½ to 3 inches long, butother sizes can be used depending on the physical size of the othercomponents, and the amount of humidity to be generated. As shown inFIGS. 14 and 18, the heater 18 may be connected to control circuitry 100controls the amount of heat and rate of heat generated by the heater 18.As shown in FIG. 18, the control circuitry 100 includes one or moretemperature sensors 102 and a control system 104 to regulate the degreeof energy supplied to the heater 18 by modulating the current suppliedto the heater via turning on/off the current and raising or lowering thecurrent. In the case of using two temperature sensors 102, thetemperature sensors 102 each independently measure the temperature ofthe core 20. The temperature signals from temperature sensors 102 arecontinuously fed to amplifiers 105. The two signals are compared witheach other and if it is determined that the difference between thesignals reaches or exceeds a predetermined level, such as 5° C., thenthe control system 104 turns off the current drivers 106 and the currentsupplied to the heater 18. The current drivers 106 are turned offbecause reaching or exceeding the predetermined level denotes that oneor both of the sensors 102 are defective and need to be replaced.

Assuming that the sensors 102 are not deemed defective, the controlsystem 104 includes four identical current drivers 106 that are inparallel with one another as shown in FIG. 18. Each driver 106 providesan output that is identical with the outputs of the other three drivers106. The control system 104 will drive each of the outputs of thecurrent drivers 106 with approximately a 25% duty cycle wave shape. Thefour drivers combined will provide approximately 100% drive to theheater 18. Each driver 106 includes a capacitor 108 of 1000 μF inparallel with a fuse 110. The capacitors 108 direct the current duringits respective 25% duty cycle away from its corresponding fuse 110. Inthe event that a single driver 106 fails, allowing continuous currentflow, the corresponding capacitor 108 will charge up and allow currentto flow through the corresponding fuse 110. In less than approximately 2seconds, the fuse 110 in the driver circuit 106 will create an opencircuit, thus preventing uncontrolled current to flow to the heater 18.

In one embodiment, the apparatus 1 can have wiring to the heater 18permanently attached. In another embodiment shown in FIG. 1, theapparatus 1 can have wiring to the heater 18 constructed with anintegral connector that can be molded into the apparatus 1 orconnected/disconnected via a one time use tab connection system. In yetanother embodiment, the apparatus 1 can have wiring to the heater 18with the terminations molded into a natural connector, so that thecabling can be plugged into it, reducing its cost. The electronic wiringused to provide power and to measure the temperature or humidity can bewired directly to the active elements and over molded. In the preferredembodiment, the output wires will be molded or inserted into the shell26 in order to make the cord detachable from the apparatus 1.

The heater 18 may be controlled by conventional heater controllers asare available on the market, such as those made by Watlow. Controllerstypically are designed to work with temperature sensing devices such asthermocouples resistance temperature detectors (RTD's) and orthermistors.

Optionally, in further embodiments, the apparatus 1 can be provided withadditional circuitry to measure humidity using a humidity sensor.Humidity sensors are available through Omega Engineering located inAtlanta, Ga., which can supply both the sensor and circuitry for readingand display. Additionally, optionally, the temperature of the gas andthe humidity of the gas could be displayed with additional circuitry. Aremote power unit, part of the insufflator, or part of any other deviceused in the Operating Room associated with endoscopic procedures couldprovide the additional circuitry to display this information. Based onthe readings, adjustments could be made on the amount of moisture fed tothe humidification material 24, or how much heat should be applied, orboth.

In one embodiment, control could also be tied to the insufflator tosupply the circuitry mentioned above. By monitoring characteristics intemperature, gas volume used, gas flow rate and/or humidity readings,the insufflator could dynamically control the variables to maintainoptimum conditions.

The core 20 may be made of, but not limited to, plastic or a sheetmetal. Some of the plastics that may be used for the core 20 includepolycarbonate, Ryton™, Vespel™, or any of the high temperature plastics.A sheet metal such as aluminum coated with a non-conductive substancemay also be used for the core 20.

As shown in FIG. 1, the apparatus 1 includes a humidification material24. The humidification material 24 both readily absorbs moisture andreadily releases it when exposed to a dry environment. Materials such asnylon and cotton are just a few of the many commercially availablefibers that can meet these requirements. The humidification material 24can have a tubular inside and outside surface. Tubular refers to asmooth surface. Yet, it is envisioned in further embodiments that thehumidification material 24 may have a patterned or varying 15 degrees ofa non-smooth surface.

As shown in FIG. 4, the humidification material 24 used in the preferredembodiment has a smooth inner surface and a serrated or star-like shapedouter surface to maximize surface area in the shortest possible linearspace. FIG. 4 shows the preferred embodiment including a first and asecond section of the humidification material 24. Each section of thehumidification material 24 is approximately an inch long with an innerchannel in intimate contact with the heater 18. Each of these serratedsections is slid over the core 20 that contains the heater 18.Preferably, a ¼ inch gap should be between the serrated sections. In oneembodiment, a plastic spacer may be inserted between the serratedsections to provide the gap. In a preferred embodiment, the first andsecond serrated sections should be set out of phase with each other toforce turbulence of the gas and increase the surface area of thematerial as it passes over the sections. Note that the first and secondserrated sections can be formed from a single serrated material bycutting the single serrated material so that the two serrated sectionsare formed. After cutting, the two serrated sections are rotatedrelative to one another until the desired phase difference between thetwo sections is achieved.

The flow of CO₂ gas over the absorbent material is affected by the shapeof the absorbent material and/or the channel within the shell 26. In oneembodiment, the absorbent humidification material 24 may becylindrically shaped and surrounded by a coil used to direct the flow ofCO₂ gas. As the CO₂ gas travels through the windings of the coil, warmthand humidity are transferred to the CO₂ gas. The external surfaces ofthe coil rest against the inside of the shell 26 forming a seal thatforces the CO₂ gas to travel through or within the coil windings.

Other shapes and sizes can be used for the humidification material 24.Manufacturers of this humidification material 24 are Pall Medicallocated in East Hills, N.Y. and Filtrona Richmond Inc. located inRichmond, Va.

The encased heater 18 elevates the temperature of the humidificationmaterial 24 thereby elevating the temperature of the moisture itcontains. The elevated temperature of the moisture leads to the creationof a vapor absorbed into the gas as it flows over the humidificationmaterial 24. Preferably, the humidification material 24 has aconfiguration that presents a high surface area to the direction of gasflow to allow increased opportunity for the moisture to evaporate intothe gas thereby humidifying the gas.

In a further embodiment, shown for example in FIG. 2, turbulence of thegas is created by the interior of the shell 26 covering thehumidification material 24 and heater 18 having a surface area that isof an irregular pattern or texture. This turbulence may be created usinga variety of structures. These structures may be located, for example,on or as part of the shell 26 or humidification material 24. Furtherexample of a structure for creating turbulence may be a spiral barrier.In additional embodiments, other structures may be incorporated, forexample, by being either attached to the humidification material 24 orinterior of the shell 26 of the apparatus 1.

The moisture applied to the humidification material 24 can containmedications or additives that will evaporate and be carried along in thehumidified gas to the patient. Levels of medication and/or fluid in thegas can be controlled by timed evaporation and adsorption rates. Fluidcould be infused by syringe, gravity feed through tubing, or by anynumber of pumps, to retain proper saturation levels.

The apparatus 1 will have a port 16 for the infusion of fluid for theproduction of moisture. Moisture may include sterile water, medication,or a mixture of fluids required for merely humidification or dispensingof medication. The port 16 can be of the standard injection port usedtypically in the medical industry, a valve, or any other device, whichcan open or close allowing for the entrance of the fluid.

The apparatus 1 includes one or more temperature sensing devices (notshown) to regulate the heater 18. Each temperature-sensing device can bea resistive temperature device (RTD), a thermister, or a thermocouple.In the preferred embodiment, a K type thermocouple is embedded insidethe heater 18 to measure its temperature. Any number of heatercontroller manufacturers such as Watlow or Hot Watt can provide thetemperature sensing and control device.

As shown in FIG. 1, the shell 26 is an oblong tube having an internalchannel, but any shape that will accommodate the internal elements ofthe device is acceptable. In the preferred embodiment, the internalchannel of the shell 26 will be smooth. In a further embodiment, anyform of surface irregularity to promote turbulence without flowrestriction is acceptable for the 15 internal channel of the shell 26.The shell 26 has an output opening 28 and an input opening 12 for thegas. The shell 26 additionally has a fluid fill port 16 for the infusionof fluid. Although, other methods of inserting the appropriate fluid ormedicine in the shell 26 are possible.

Overall length of the preferred embodiment will be between 3½ and 4inches. Preferably, the apparatus 1 will weigh approximately fourounces. The shell 26 can be made of any suitable material, for example,metal or plastic.

In additional embodiments, as shown in FIG. 3, a humidity sensor 34 maybe included in the apparatus 1. Appropriate humidity sensors 34 can beobtained from Omega Corporation located in Atlanta, Ga.

Optionally, in further embodiments, in addition to the temperaturesensing device described above, an external temperature sensing device32 can be inserted in the insufflation tubing 10 just outside of the gasoutlet 28. The same types of temperature sensing devices internal to theapparatus 1 as described above can be used. This device 32 measures thedownstream temperature of the gas.

The temperature of the gas is related to the temperature of the heater18. The temperature sensing device located within the heater 18 measuresthe temperature of the heater 18. The temperature of the gas is notdirectly measured. Rather, the resulting temperature of the gascorrelates to the temperature of the heater.

The warmed and humidified gas leaves the apparatus 1 through a gasoutlet 28. The gas outlet may be a series of holes. The gas then entersthe insufflation tubing 10 for possible delivery to a patient.

Another embodiment of a gas humidification apparatus is shown in FIGS.5-12. In a manner similar to the devices of FIGS. 1-4, the gashumidification apparatus 201 can be used in conjunction with aninsufflation device. In particular the gas humidification apparatus 201is located downstream from a gas source for the insufflation device. Thegas humidification apparatus 201 may be constructed as a re-useable ordisposable product.

As shown in FIGS. 5, 6, 9 and 10, a gas inlet port 212 is attachedthrough a side portion of a front cap 213 of the gas humidificationapparatus 201. In addition, an inlet port 215 is attached through acentral portion of the front cap 213. The inlet port 215 allows forelectrical components and wiring to be inserted into the gashumidification apparatus 201. The gas humidification apparatus 201 canbe modified so that the ports 212 and 215 are interchanged with oneanother.

As shown in FIG. 5, the cap 213 includes an annular metallic heaterhousing 217 that is attached thereto. The heater housing 217 is in fluidcommunication with the gas inlet port 212. The heater housing 217contains a heater cartridge that is well known in the art. Whenactivated the heater cartridge heats up the interior and body of theheater housing 217 so that gases within and outside the heater housing217 are heated. The heater housing 217 also includes a plurality ofcircular holes 219 having a diameter of approximately 0.1″ (0.254 cm).Other shapes and sizes for the holes 219 are possible, such astriangular and square shaped openings. When gas flows into the gashumidification apparatus 201 via the gas inlet port 212, the gas flowsinto the heater housing 217, where it is heated if necessary, and thenflows out of the holes 219. As shown in FIG. 5, there are approximatelysixteen holes 219 that are arranged equidistantly from one another alongan annular ring. The holes 219 of the heater housing 217 improve therate of heating of the gas within the gas humidification apparatus 201and create turbulence for the gas flowing within the gas humidificationapparatus 201.

Two of the holes 219 preferably have their own RTD sensor. These sensorsoperate in the same manner as the temperature sensors for theembodiments of FIGS. 1-4. In particular, the temperature measured by thetwo sensors are compared with one another to determine if one or both ofthe sensory is defective.

As shown in FIG. 5, a rear cylindrical portion 223 of the heater housing217 is snugly inserted into a cylindrical central opening of ahumidification material 224 that is preferably made of the same materialas the humidification materials 24 described previously with respect toFIGS. 1-4. A washer 221 is fitted over the rear portion 223 and abutsagainst the rear face of the humidification material 224 and acts as astop in that it prevents the humidification material 224 from slippingoff of the rear portion 223 and being wedged into an outlet 228.

In an alternative embodiment, the gas humidification apparatus 201 canfurther include a plate 225 positioned between the front or proximal endof the humidification material 224 and the heater housing 217. Since theholes 219 face the front end of the humidification material 224, theplate 225 allows the gas to flow along the exposed side of thehumidification material. Note that the gas will flow along the side ofthe humidification material with or without the presence of the plate225.

As shown in FIG. 12, the humidification material 224 has a star-likepattern with ten to twelve points that aid in generating turbulence inthe gas within the gas humidification apparatus 201 in a similar mannerthat the humidification material 24 of FIGS. 1 and 4 do.

In an alternative embodiment, a second humidification material 224 maybe spaced from the first humidification material by a spacer and out ofphase with the first humidification material in the same manner asdescribed previously with respect to the embodiment of FIGS. 1 and 4.

As shown in FIG. 5, the assembled humidification material 224 and washer221 and the inlet port 215 and the heater housing 217 are inserted intoa housing or shell 226. After insertion, the front cap 213 is screwed onor snap fit onto the heater housing 217. The housing 226 is made of asuitable material, such as plastic or metal, and has a downstream outlet228 that allows the gas to flow outside of the housing 226.

As shown in FIGS. 5-9 and 11, the housing 226 includes a port 216 thatallows fluid to be infused by syringe, gravity feed through tubing, orby any number of pumps, to the humidification material 224. The fluidsinfused may include sterile water, medication, or a mixture of fluidsrequired for merely humidification or dispensing of medication. Theinterior end of the port 216 is positioned so that infused fluids dripinto the housing 226 and are soaked up by the entire humidificationmaterial 224 by capillary action. The port 216 is similar to the port 16described previously with respect to the embodiments of FIGS. 1-4.

As shown in FIGS. 5-9, the housing 226 is inserted into a sleeve orshroud 230 so that the port 216 is slid along a slit 232 formed in thesleeve 230 and the outlet 228 extends through a rear opening 234 of thesleeve 230. The sleeve 230 is snap fit to the housing 226. The sleeve230 is made of a thermal insulation material that retains the heatwithin the housing 226 so that a person can handle the sleeve 230without fear of being exposed to excessive heat and withoutsignificantly heating up the ambient atmosphere.

Note that the sleeve 230, the housing 226 and the humidificationmaterial 224 may be disposable while the cap 213 and its attached heaterhousing 217 may be reusable.

The gas humidification apparatus 201 may include the temperaturesensors, humidity sensors and control circuitry previously describedwith respect to the embodiments of FIGS. 14 and 18 so that thetemperature and humidity of the gas flowing within the apparatus anddelivered to a patient via outlet 228 is controlled.

Another embodiment of a gas humidification apparatus is shown in FIGS.13-17. The gas humidification apparatus 301 essentially has the samestructure as the gas humidification apparatus 201 of FIGS. 5-12 and solike components will be designated with like numerals. One difference isthat a second port 302 is added to the housing 226. The second port 302is positioned between the humidification material 224 and the outlet 228so as to allow a distal end of a catheter 304 to be inserted into theport 302. Depending on the intended material to be delivered to thepatient, the distal end of the catheter 304 may be positioned within theport 302, within the interior of the gas humidification apparatus 301 orwithin a tube attached to the outlet 228 and in fluid communication witha section of a patient, or within the section of the patient. An exampleof a catheter that can be inserted into the gas humidification apparatus201 is the catheter described in U.S. Pat. No. 5,964,223, the entirecontents of which are incorporated herein by reference. Other devicescan be inserted into the port 302 in a similar manner as described abovewith respect to catheter 304, such as a lumen and an endoscope.Furthermore, gases, liquids, aerosols and medicines may be conveyed to apatient by a tube or other know dispensing devices inserted through theport 302 and exiting out of the outlet 228 into the patient. Note thatthe materials dispensed into the port 302 by the above-mentioneddispensing devices may have properties that raise the humidity of thegas within the interior of the gas humidification apparatus 301.

The gas humidification apparatus 301 may include the temperaturesensors, humidity sensors and control circuitry previously describedwith respect to the embodiments of FIGS. 1-4 and 18 so that thetemperature and humidity of the gas flowing within the apparatus anddelivered to a patient is controlled.

In each of the devices for humidifying and/or warming a gas describedpreviously with respect to FIGS. 1-18, it is desired that the flowinggas achieves a humidity that ranges from approximately 80 to 100 percenthumidity and achieves a temperature that ranges from approximately 90 to105 degrees Fahrenheit at a constant flow rate of approximately 20liters per minute.

The embodiments of the invention disclosed herein are presentlyconsidered to be preferred, various changes and modifications can bemade without departing from the spirit and scope of the invention. Asnoted, the discussion above is descriptive, illustrative and exemplaryand is not to be taken as limiting the scope defined by any appendedclaims, and all changes that come within the meaning and range ofequivalents are intended to be embraced therein.

1. A gas apparatus for use in a medical procedure comprising: a housingdefining a chamber having a gas inlet and a gas outlet: a heater forwarming a gas flowing through the chamber; and a humidification materialadjacent to the heater and comprising at least two gas flow channels forflowing gas over the humidification material.
 2. The apparatus of claim1, wherein the heater comprises a heater housing in fluid communicationwith the gas inlet.
 3. The apparatus of claim 2, wherein the heaterhousing comprises a plurality of holes.
 4. The apparatus of claim 1,wherein the humidification material comprises a cylindrical centralopening.
 5. The apparatus of claim 1, wherein the heater comprises acylindrical portion for insertion into the cylindrical central opening.6. The apparatus of claim 1, wherein the medical procedure is alaparoscopic procedure.
 7. The apparatus of claim 1, wherein thehumidification material comprises eight gas flow channels.
 8. Theapparatus of claim 1, wherein the plurality of holes directs the gas toflow into the at least two gas flow channels.
 9. A method for using agas apparatus in a medical procedure, the method comprising: receiving agas at a gas inlet of a chamber, the chamber defined by a housing of thegas apparatus; warming the gas with a heater of the gas apparatus as thegas flows through the chamber to a gas outlet of the chamber; andhumidifying the gas as the gas flows through the chamber in at least twogas flow chambers of a humidification material positioned adjacent tothe heater in the chamber.
 10. The method of claim 9, furthercomprising: receiving gas from the gas inlet at a heater housing of theheater, where the heater housing is in fluid communication with the gasinlet.
 11. The method of claim 10, wherein the heater housing comprisesa plurality of holes through which the gas exits the heater.
 12. Themethod of claim 11, further comprising: directing the gas exiting theheater into the at least two gas flow chambers of the humidificationmaterial using the plurality of holes of the heater housing.
 13. Themethod of claim 9, wherein the humidification material comprises acylindrical central opening.
 14. The method of claim 13, wherein theheater comprises a cylindrical portion for insertion into thecylindrical central opening.
 15. The method of claim 9, wherein themedical procedure is a laparoscopic procedure.
 16. The method of claim9, wherein humidifying the gas as the gas flows through the chamber inat least two gas flow chambers of the humidification material comprises:humidifying the gas as the gas flows through eight gas flow channels ofthe humidification material.